<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>demo</title>
  <script type="text/javascript" src="./vue.js"></script>
</head>

<body>
  <div id="app">
    <template v-if="score > 90">
      <h1>成绩是</h1>
      <p>A</p>
    </template>

    <template v-else-if="score > 70">
      <h1>成绩是</h1>
      <p>B</p>
    </template>

    <template v-else-if="score > 50">
      <h1>成绩是</h1>
      <p>C</p>
    </template>

    <template v-else>
      <h1>成绩是</h1>
      <p>D</p>
    </template>

  </div>
</body>
<script type="text/javascript">
  Vue.config.productionTip = false;
  const vm = new Vue({
    el: "#app",
    data() {
      return {
          score: null
        }
    }
  })
</script>

</html>